Though it has it's occasional flaws (some overstatement) this is generally a terrific political thriller.
A young Palestinian radical is put through the emotional, moral and physical wringer after being blackmailed into becoming an informer (or at least professing to) for the Israelis, following an arrest that could put him in jail for life. While Abu-Assad's sympathies clearly lie with the Palestinians, his characters and situations are much more complex and human than good guys and bad guys. He sees the damage that being in a constant state of war and occupation does to both sides.
Beyond that, this is not a 'political' film first. It's complex web of betrayal, love, fear, bravery, and paranoia could be anywhere two sides are facing off in a morally and politically complex situation, especially where one side is a guerrilla uprising, the other an established government. It could be Ireland and the IRA, or South Africa in the more militant days of the ANC. The beauty and terror of Abu-Assad's film is that it's about people not ideology. And the reality that people on both sides are capable of great good and great evil, often for reasons personal as much as political. I happened to see this within days of the also critically acclaimed "Bethlehem" which tells a remarkably similar tale, but from an Israeli point of view. Seeing both heightened the power of each -- for where they overlapped and where they differed. I'd recommend seeing both to anyone interested in good, human thrillers and who is interested in examining the middle east conflict in more than simple 'right and wrong' terms.